1. Field of the Invention
The present invention relates to a printhead board, a printhead, and a printing apparatus.
2. Description of the Related Art
For some printing apparatuses such as an inkjet printer, a printhead for discharging ink is detachable from a printing apparatus. A printing apparatus and a printhead have connection terminals, respectively, through which the printing apparatus and the printhead are connected to each other. Japanese Patent Laid-Open No. 2007-008064 proposes a technique in which a printhead outputs a signal to a printing apparatus in accordance with a signal supplied from the printing apparatus in order for the printing apparatus to determine whether the printing apparatus and the printhead are connected to each other. The printhead has a connection terminal dedicated for outputting a signal indicating whether the printhead is connected to the printing apparatus.
Furthermore, Japanese Patent Laid-Open No. 2004-090246 proposes a technique in which a resistance element (rank heater) with the same arrangement as that of a heat generation element for discharging ink is formed on a printhead board and a printing apparatus measures the resistance value of the resistance element to set optimum driving conditions for the heat generation element. Both ends of the resistance element of the printhead are connected to dedicated connection terminals, respectively, and the printing apparatus measures the resistance value between the two connection terminals.